Method and apparatus for testing of cigarettes or the like

ABSTRACT

A TESTING CONVEYOR FOR CIGARETTES, PARTICULARLY FILTER CIGARETTES, WHEREIN THE ROTOR IS FORMED WITH AXIALLY PARALLEL PERIPHERAL FLUTES FOR CIGARETTES WHICH ARE CAUSED TO MOVE SIDEWAYS PAST A TESTING STATION WHERE A STREAM OF TESTING GAS IS PASSED THROUGH THEIR WRAPPERS. THE ENDS OF WRAPPERS ARE SEALED DURING TRAVEL PAST THE TESTING STATION BY PAIRS OF ANNULAR SEALING FACES AT LEAST ONE OF WHICH IS PROVIDED ON A TILTABLE SEALING ELEMENT SHARING THE MOVEMENT OF THE ROTOR AND CAPABLE OF CHANGING THE INCLINATION OF ITS SEALING FACE SO THAT THE LATTER IS MOVE INTO THE PLANE OF THE ADJOINING END SURFACE OF THE WRAPPER. IN THIS WAY, THE TITLTABLE SEALING ELEMENT CAN PROPERLY SEAL AN END SURFACE WHOSE PLANE IS NOT EXACTLY NORMAL TO THE AXIS OF THE CIGARETTE.

U. HEITMANN Jan. 19, 1971 METHOD AND APPARATUS FOR TESTING OF CIGARETTES OR THE LIKE 2 Sheets-Sheet 1 Filed June :20, 1969 ATTORNEY METHOD AND APPARATUS FOR TESTING OF CIGARETTES OR THE LIKE Filed June :20, 1969 U. HEITMANN 2 Sheets-Sheet 2 @Q T wk M, Q E w%\ \N II: 5 M N I T! 5. mm

"kmLa-w ATTORNEY US. CI. 73-41 United States Patent 3,555,883 METHOD AND APPARATUS FOR TESTING OF CIGARETTES OR THE LIKE Uwe Heitmann, Hamburg, Germany, assignor to Hanni- Werke Korber & Co. KG, Hamburg, Germany Filed June 20, 1969, Ser. No. 835,103 Claims priority, application Germany, June 25, 1968,

Int. cl. Glllm 3/02 20 Claims ABSTRACT OF THE DISCLOSURE A testing conveyor for cigarettes, particularly filter cigarettes, wherein the rotor is formed with axially parallel peripheral flutes for cigarettes which are caused to move sideways past a testing station where a stream of testing gas is passed through their wrappers. The ends of wrappers are sealed during travel past the testing station by pairs of annular sealing faces at least one of which is provided on a tiltable sealing element sharing the movement of the rotor and capable of changing the inclination of its sealing face so that the latter is moved into the plane of the adjoining end surface of the wrapper. In this way, the tiltable sealing element can properly seal an end surface whose plane is not exactly normal to the axis of the cigarette.

BACKGROUND OF THE INVENTION The present invention relates to a method and apparatus for testing of plain cigarettes, filter cigarettes, plain or filter-tipped cigars, cigarillos, cheroots, filter rod sections, or analogous rod-shaped articles wherein an openended tubular wrapper of cigarette paper, cork, tobacco leaf, reconstituted tobacco foil or the like surrounds a filler of gas-permeable material, for example, a filler of shredded tobacco and/or one or more filter materials. More particularly, the invention relates to a method and apparatus for testing of rod-shaped articles which move sideways and whose integrity is tested by means of a gaseous fluid which is caused to pass through the fillers within the confines of their wrappers.

It is already known to test cigarettes during travel with a rotary conveyor on which the cigarettes travel sideways. The conveyor is provided with axially movable sealing elements which flank flutes for cigarettes and are movable toward and away from each other to thereby engage or release the adjoining end surfaces of wrappers. Testing fluid is passed through the sealing elements and through the fillers while the sealing elements engage and seal the adjoining end surfaces of the wrappers. A drawback of such proposal is that the sealing elements furnish a satisfactory sealing action only in the event that the planes of the end surfaces of cigarettes are exactly normal to the axes of cigarettes unless, of course, the sealing elements are caused to effect excessive deformation of cigarette ends in order to insure satisfactory sealing action with end surfaces of perfect cigarettes as well as of those cigarettes which are cut at a bias. Even slight deformation of cigarette ends is highly undesirable, not only because it affects the passage of smoke but also because it detracts from the appearance of cigarettes.

It is also known to mount one of each pair of axially aligned sealing elements on springs so that it can yield in response to engagement with the adjoining end of a cigarette. Such mounting of sealing elements is advantageous because it can compensate for eventual differences in the length of successively tested cigarettes; however, the springs cannot insure proper sealing action between axially reciprocable sealing elements and inclined end surfaces of tested cigarettes.

SUMMARY OF THE INVENTION An object of my invention is to provide a method and apparatus for efiicient and reliable pneumatic testing of cigarettes or analogous rod-shaped articles in such a way that the interior of the wrapper on an article is properly sealed from the atmosphere even if one or both end surfaces of the tested article are not exactly normal to its axis.

Another object of the invention is to provide a method according to which cigarettes or like rod-shaped articles which are of desired size and shape save for minor defects in the inclination of their end surfaces can be tested with the same efliciency as those articles whose end surfaces have an optimum inclination.

A further object of the invention is to provide an apparatus which can test randomly supplied perfect and imperfect cigarettes (as regards the inclination of their end surfaces) with the same efiiciency, at a high speed, with greater reliability than presently known testing apparatus, and which can test the cigarettes without danger of excessive deformation of their ends.

An additional object of the invention is to provide a novel testing conveyor for use in the above outlined testing apparatus.

Still another object of the invention is to provide the testing conveyor with novel means for sealing the ends of wrappers on cigarettes or like rod-shaped articles.

An ancillary object of the invention is to provide novel and improved sealing devices which can be installed in or on presently known testing conveyors to thereby enhance the versatility, reliability and effectiveness of such conveyors.

A further object of the invention is to provide a testing conveyor which can properly transport and seal cigarettes or like rod-shaped articles of optimum length, of excessive length, of less than optimum length, of optimum configuration (as regards the inclination of their end surfaces) and of a configuration which deviates from the optimum configuration.

The method of my invention comprises the steps of moving an article sideways between travelling first and 'second apertured sealing faces which are advanced at the same speed and are adjacent to the end surfaces of the tubular wrapper, moving at least the first sealing face toward the second sealing face so that each sealing face engages one end surface of the wrapper therebetween, changing the inclination of at least one sealing face to move it into the plane of the adjoining end surface whenever the one sealing face is in less than full contact with the adjoining end surface, and passing a testing fluid between the apertured sealing faces by way of the wrapper therebetween. The aforementioned inclination changing step preferably comprises reducing the distance between the sealing faces to such an extent that the corresponding end surface of the wrapper automatically (i.e., forcibly) changes the inclination of the one sealing face. The configurations of the sealing faces are preferably such that they remain at least slightly spaced from the respective ends of the filler upon completion of the inclination changing step so that each sealing face is in substantially linear contact with the respective ends of the article, i.e., that each sealing face is in full sealing engagement with the adjoining annular end surface of the wrapper. The first sealing face is preferably moved in axial direction of the article which moves with and is located between the sealing faces so that the article is shifted axially in response to axial displacement of the first sealing face and is thereby caused to engage the second sealing face.

The novel features which are considered as characteristic of the invention are set forth in particular in the appended claims. The improved testing apparatus itself,

however, both as to its construction and its mode of operation, together with additional features and advantages thereof, will be best understood upon perusal of the following detailed description of certain specific embodiments with reference to the accompanying drawing.

BRIEF DESCRIPTION OF THE DRAWING FIG. 1 is a fragmentary axial sectional view of a testing apparatus whose conveyor is constructed and assembled in accordance with a first embodiment of my invention;

FIG. 2 is an enlarged axial sectional view of a detail in a slightly modified testing conveyor;

FIG. 3 is a fragmentary axial sectional view of a testing apparatus having a different testing conveyor;

FIG. 4 is a fragmentary axial sectional view of a fourth testing conveyor; and

FIG. 5 is a fragmentary elevational view as seen in the direction of arrow V in FIG. 4.

DESCRIPTION OF THE PREFERRED EMBODIMENTS Referring to FIG. 1, there is shown a portion of a testing apparatus which comprises a testing conveyor 1 serving to transport a succession of filter cigarettes C sideways past a testing station. The conveyor 1 comprises a rotary conveying member 2 (hereinafter called rotor) and a stationary part 3 (hereinafter called stator). The rotor 2 includes a cylinder 4 which is rotated about a fixed horizontal axis, preferably about the axis of a fixed horizontal shaft (not shown) which is connected to the stator 3. The left-hand end portion of the cylinder 4 is connected with a disk-shaped flange 6 which constitutes a first sealing unit, and the right-hand end portion of the cylinder is partially surrounded by and aflixed to a ring-shaped second flange 7 of U-shaped profile. The periphery of the cylinder 4 is provided with rows of axially aligned projections or ribs 8 which define receiving means or flutes 9 for accommodation of cigarettes C during transport toward, past and beyond the testing station. The rows of receiving means or flutes 9 (only one such row is shown in FIG. 1) are equidistant from each other, as considered in circumferential direction of the cylinder 4.

The right-hand end face of the flange 6 is formed with a set of axially parallel blind bores 11 each of which registers with one row of flutes 9 and each of which forms part of a passage for a testing fluid (preferably air) to a testing unit T of known design. Each passage of the flange 6 further comprises a radially extending bore 12 which communicates with the respective 'bore 11 and extends outwardly to the smooth cylindrical peripheral surface 13 of the flange. Those apertured portions (44) of the right-hand end face of the flange 6 which surround the open ends of the blind bores 11 constitute sealing faces for the adjoining annular end surfaces of wrappers of the filter cigarettes C, namely, for the tobacco-containing ends of such cigarettes. The peripheral surface 13 of the flange 6 is engaged by the concave surface of a stationary shoe 14 which is biased against the surface 13 by one or more springs (not shown) and is located at the testing station station. The concave surface of the shoe 14 is formed with a circumferentially extending chamber 16 whose length determines the length of the testing station and which communicates with the testing unit T -by way of a nipple 17 and a hose or conduit 17a. The inner end of the nipple 17 communicates with the chamber 16. When the rotor 2 is driven by a transmission or the like, not shown, the bores 12 of successive passages in the flange 6 communicate with the chamber 16 (and hence with the testing unit T) during travel past the testing station.

The right-hand flange 7 resembles a spool or reel and includes two axially spaced ring-shaped portions 7a, 7b. These ring-shaped portions are provided with registering axially parallel bores 70, 7d which accommodate axially reciprocable tubular connectors 18. Each connector 18 has an axially extending bore or passage 18a which registers with a row of flutes 9 and with one of the blind bores 11. The left-hand end portion or tip 18b of each connector 18 is sealingly fitted into one end of an elastically deformable tubular coupling element 41 (for example, a piece of rubber-hose) which serves to couple the connector 18 with a substantially rigid sealing element 42 having a concave sealing face 43 facing the nearest flute 9. The parts 18, 41 and 42 together constitute a second sealing unit which rotates with the flange 7 and whose elements 42 serve to sealingly engage the open ends of filter tips F on the cigarettes C. The stiffness of each sealing element 42 is such that its material cannot be deformed by the filter tip F of a cigarette C. However, the stiffness of elastic coupling elements 41 is much less so that each element 41 can be indirectly deformed by a filter tip F. At the same time, the coupling elements 41 are sufficiently rigid to normally maintain the associated sealing elements 42 in predetermined positions, namely, in optimum positions for engagement with the open end surfaces of wrappers of filter tips F on cigarettes C which are accommodated in the registering row of flutes 9. Deformation of a coupling element 41 will take place if the plane of the exposed annular end surface of a filter tip F is not exactly normal to the axis of the respective cigarette C or if such end surface has been deformed during travel from the filter tipping machine to the testing station. The concaveness or conicity of the sealing faces 43 is advantageous because such configuration of the sealing faces insures that the properly engaged and sealed Wrapper of the filter tip F is in mere linear engagement with the corresponding sealing element 42, namely, that only the ring-shaped end surface of the wrapper of the filter tip F engages the sealing face 43. L

Each connector 18 has a circumferential groove 19 which is located in the annular recess between the ringshaped portions 7a, 7b of the flange 7 and which receives with clearance the prongs at the bifurcated end of a motion transmitting or displacing fork 21. A helical spring 22 which surrounds the connector 18 reacts against the fork 21 and serves to bias the connector 18 (with elements 41, 42) in a direction to the left, as viewed in FIG. 1. The axial movability of the connector 18 with reference to the fork 21 is determined by the axial clearance between the ends of the groove 19 and the prongs of the fork. The left-hand end convolution of the spring 22 bears against an annular shoulder 23 of the respective connector 18. Each fork 21 is affixed to an axially reciprocable shaft 24 which is guided in axially parallel bores of portions 7a, 7b and carries a roller follower 27 tracking the face of a fixed displacing cam 28. A helical spring 26 which reacts against the ring-shaped portion 7a bears against the fork 21 and biases the roller follower 27 against the face of the cam 28. The configuration of the face on the cam 28 is such that it can move successive roller followers 27 axially of the conveyor 1 toward the flange 6 in predetermined angular positions of the rotor 2 to thereby move the faces 43 of sealing elements 42 into engagement with the end surfaces of wrappers on filter tips F and to simultaneously urge the left-hand end surfaces of wrappers of cigarettes C against the sealing faces 44 on the flange 6. The cam 28 is fixedly secured to or forms an integral part of the stator 3.

The ring-shaped portion 7b of the flange 7 is secured to a ring 29 which is formed with a set of axially parallel bores 31 each of which registers with the axial bore 18a of a connector 18. The ring 29 is adjacent to a ring-shaped valve plate 32 which is mounted on the stator 3 and is free to perform limited axial movements with reference to the rotor 2. A radially extending pin 33 of the stator 3 holds the valve plate 32 against rotation with the ring 29. One or more springs (not shown) are provided to permanently bias the valve plate 32 toward the ring 29 and to thereby maintain the right-hand end face of the ring 29 in sealing engagement with a gasket 34 which is aflixed to the left-hand end face of the valve plate 32. The aforementioned springs which bias the valve plate 32 axially are mounted in and react against the stator 3. The parts 32, 34 are provided with registering arcuate slots 36 which are located at the testing station and communicate with a nipple 37. The latter is connected with a source S of pressurized gaseous fluid by a flexible conduit or hose H which contains a suitable regulating valve V. When the rotor 2 is driven so that the ring 29 rotates with reference to the stator 3, successive bores 31 move into temperary communication with the slots 36.

The flange 7 further supports a ring-shaped cam 38 which overlies the outer side of the recess between the portions 7a, 7b and is provided with outwardly extending projections 39 cooperating with a contactless initiator to form therewith a timer. Furthermore, the right-hand end face of the cam 38 is grooved to receive ring-shaped ribs on the left-hand end face of the stator 3 whereby the parts 3, 38 form a labyrinth seal which prevents penetration of dust, moisture or other foreign matter into the compartments for the roller followers 27.

The operation:

Theconveyor '1 is rotated in synchronism with a supply conveyor (not shown) which supplies filter cigarettes C into successive rows of flutes '9 on the cylinder 4. Such cigarettes are preferably retained in their flutes 9 by suction, for example, in a manner as disclosed and shown in Pat. No. 3,408,858 to Kaeding et al. Said patent also shows a supply conveyor, av receiving conveyor which receives satisfactory cigarettes from the testing conveyor, and a receptacle which intercepts defective cigarettes.

Defective cigaretres are preferably ejected from their flutes 9 by one or more jets of compressed airwhich are admitted into the corresponding flutes by the testing unit T in a manner which forms no part of the present invention. This invention is mainly concerned with the design of the testing conveyor 1, namely, with the design of those parts of the testing conveyor which insure proper sealing of both ring-shaped end surfaces of the wrapper of each cigarette C. which is transported past the testing station, i.e., through the zone between the slots 36 of the parts 32, 34 and the chamber 16 of the shoe 14.

Theaforementioned supply conveyor delivers cigarettes C in such a Way that the filter tip F of each cigarette is adjacent to'the apertured face 43 of the respective sealing element -42. At the transfer station between the testing conveyor 1 and the supply conveyor, the face of the displacing cam 28 permits the springs 26 to expand so that the sealing elements 42 are located in their right most positions and their sealing faces 43 define with the sealing faces 44 'Of the flange 6 gaps of a width which exceeds thelength'of a cigarette C so that the cigarettes can enter the corresponding rows of flutes 9 without any obstruction on the part of the sealing elements 42 and flange 6. As. a freshly transferred cigarettte C moves past and beyond the transfer station, the face of the cam 28 causes the corresponding follower 27 to shift the connector 18 toward the flange 6 whereby the sealing face 43 of the element 42 engages the end surface of the wrapper of the filter tip F. During the next-following stage of rotation of the cylinder 4, the cam 28 effects further leftward axial movement of the connector 18 so that the left-hand end surface of the wrapper of the cigarette C engages the sealing face 44, i.e., the face 43 of the sealing element 42 shifts the cigarette axially toward the flange, 6. The shaft 24 continues to move to the left and the' fork 21 effects compression of the relatively weak spring 22 so that the latter biases the sealing face 43 against, the end surface of the wrapper of the filter F. If the plane of the end surface of the wrapper of the filter tip F is not exactly normal to the axis of the cigarette C, the end surface of the wrapper of the filter tip F is in mere point contact with the sealing face 43 until the coupling element 41 yields to the bias of the spring 22 and allows the sealing element 43 to change its inclination whereby'the face 43 moves into an optimum sealing engagement with the inclined end surface of the wrapper of the filter tip F. The conical shape of the sealing face 43 insures that the optimum contact between such sealing face and the adjoining end surface of the wrapper of the filter tip F takes place along a circle. This is advantageous for several reasons, mainly because the sealing face 43 engages the marginal portion of the adjoining end of the filter tip (i.e., the end surface of the wrapper with a substantial force to insure an optimum sealing action. The left-hand end of the cigarette C (namely, that end which is filled with tobacco shreds) is softer than the filter tip F so that it yields slightly in response to the biase of the spring 22 and moves the end surface of the wrapper into satisfactory engagement with the sealing face 44 of the flange 6. This is the reason why the conveyor 1 need not necessarily be provided with two axially movable sealing units, i.e., that the parts 18, 4 1, 42 need not be provided on the flange 6. However, it is clear that the conveyor 1 can be equipped with a second axially movable sealing unit which is then mounted in the flange 6 substantially in the same way as desccribed for the parts 18, 41, 42 shown in the flange 7 of FIG. *1.

Both end surfaces of the wrapper of a cigarette C in a row of flutes 9 are properly engaged and sealed from the atmosphere by the apertured sealing faces 43, 44 before the cigarette reaches the testing station. When the corresponding radial bore 12 moves into registry with and travels along the chamber 16 of the shoe 14, the bore 18a of the corresponding connector 18 communicates with the slots 36 of the valve plate 32 and gasket 34. Thus, a stream of testing fluid can flow from the source S through the wrapper of the cigarette C and to the testing unit T. The pressure of fluid which reaches the unit T is indicative of the condition of the cigarette C. Thus, if the pressure is too low, the cigarette C must have a leak, either along the seam between the overlapping edges of its wrapper, in the region where the filter tip F is connected to the tobacco rod, or elsewhere. If the pressure of air which reaches the unit T is too low, this can indicate that the tobacco filler of the cigarette C is too dense. The testing unit T then produces an appropriate signal which is communicated to an ejecting device serving to segregate defective cigarettes from satisfactory cigarettes, either immediately upon detection of a defective cigarette (i.e., while such cigarette travels past the testing station), from that porion of the esting conveyor 1 which is locatedpast the testing station, or from a further conveyor which receives cigarettes from the conveyor *1. It is also possible to design the testing unit T in such a way that it segregates satisfactory cigarettes from defective cigarettes and permits the defective cigarettes to travel with the testing conveyor past and beyond the testing station to a transfer station where the defective cigarettes are dumped into a collecting receptacle or are otherwise collected for transport to a breaking device which salvages the tobacco shreds.

When a cigarette C advances beyond the testing station, the corresponding spring 26 is permitted to expand and to move the respective parts 18, 41, 42 in a direction to the right and away from the filter tip F. The cigarette is then free to leave its row of flutes 9 and is transported to a further destination, depending on the nature and presence or absence of a signal from the testing unit T. Satisfactory cigarettes are normally transported to a collecting station where they are transferred into chargers or trays or are immediately delivered into a packing machine which assembles them in groups of twenty cigarettes '(or more or less) and provides such groups with one or more envelopes to form a pack. Defective cigarettes are manipulated in a manner as described above.

FIG. 2 illustrates a portion of a modified movable sealing unit which can be utilized in the testing conveyor of FIG. 1 as a substitute for the illustrated sealing unit including the parts 18, 41, 42. This modified sealing unit comprises connectors 48 each corresponding substantially to the connector 18, sealing elements 47 each corresponding substantially to the element 41, and elastically deformable tubular coupling elements 46. The sealing element 47 of FIG. 2 forms with the elongated guide portion or tip 49 of the connector 48 a universal joint or swival joint which enables the head of the element 47 to assume a practically infinite number of positions in response to deformation of or under the bias of the coupling element 46. The left-hand end of the guide portion 49 is of spherical shape and extends into a sleeve-like socket of the sealing element 47. This enables the latter to pivot in all directions with reference to the spherical end of the guide portion 49. The coupling element 46 permits the sealing element 47 to move axially of the guide portion 49. If the conveyor 1 of FIG. 1 employs a movable sealing unit of the type shown in FIG. 2, the springs 22 may (but need not) be dispensed with because the elasticity of the coupling element 46 enables the sealing element 47 to move axially toward the connector 48. Thus, the connector 48 can continue to move toward the filter tip of a cigarette when the concave apertured sealing face of the element 47 already engages the end surface of the wrapper of the filter tip.

FIG. 3 illustrates a portion of a testing conveyor 51 which is in some respects similar to or identical with the conveyor 1 of FIG. 1. All such parts of the conveyor 51 which are clearly analogous to corresponding parts of the conveyor 1 are denoted by similar reference numerals plus 50. Thus, the conveying member or rotor of the conveyor 51 is numbered 52, the stator 53, and so one. The main difference is that the testing conveyor comprises two axially movable sealing units, namely, one unit at each axial end of its rotor 52. The right-hand sealing unit comprises unitary connectors 68 each of which is similar to the connector 18 of FIG. 1 with the exception that the tip 18a is omitted and that the apertured sealing face 93 is provided at its left-hand end. This connector 68 is reciprocable axially of the flange 57 but the prongs of the fork 71 extend into its groove 69 without any clearance so that the spring 22 of FIG. 1 is omitted, i.e., the connector 68 is positively coupled to the respective shaft 74 and follower 77.

The left-hand sealing unit of the testing conveyor 51 comprises sealing elements 92 each of which is mounted in the central portion of an elastically deformable coupling element here shown as an annular diaphragm 91 whose marginal portion is sealingly secured to the flange 56. Each axially parallel bore 61 of the flange 56 has an enlarged outer end portion or recess or chamber 101 of circular outline whose diameter is a multiple of the diameter of a filter cigarette C. The diaphragm 91 extends across and seals the open end of the recess 1 01. The sealing element 92 has an axial bore whose diameter is somewhat less than the internal diameter of the adjoining end surface of the wrapper of the filter tip F of the cigarette C; its preferably (but not necessarily) conical sealing face is shown at 94. When the diaphragm 91 is not stressed, the axis of the sealing element 92 coincides with the axis of the registering connector 68. Thus, if the sealing face 94 of the at 94. When the diaphragm 91 is not stressed, the axis of a cigarette C in the corresponding row of flutes 59 when the filter tip F of the cigarette does not engage the sealing face 94 or when the left-hand end surface of the wrapper of the filter tip F is exactly normal to the axis of the cigarette.

The operation of the testing conveyor 51 is as follows:

Cigarettes C are delivered to successive rows of flutes 59 in the same way as described in connection with FIG. 1, excepting that the filter tips F of cigarettes in the flutes 59 are adjacent to the flange 56. As a freshly transferred cigarette C advances toward the testing station, the face of the displacing cam 78 causes the corresponding connector 68 to move axially toward the flange 56 whereby the sealing face 93 engages the right-hand end surface of the wrapper for the tobacco-containing portion of the cigarette C and shifts the latter axially so that the end surface of the wrapper of the filter tip F engages the sealing face 94 of the sealing element 92. Since the connector 68 is positively coupled to the corresponding follower 77, the connector moves axially to the extent determined by the configuration of the face of the cam 78, i.e., the sealing face 93 cannot yield. The filter tip F presses the sealing element 92 into the recess 101 to deform the diaphragm 91. If the plane of the end surface of the wrapper of the filter tip F is not exactly normal to the axis of the cigarette C, the diaphragm 91 permits the sealing element 92 to change its position of inclination so that the sealing face 94 moves into an optimum sealing engagement with the adjacent end surface of the tubular wrapper. Since the diameter of the bore in the sealing element 92 is only slightly less than the diameter of the filter tip F, the sealing face 94 is held in linear contact with the wrapper of the filter tip even if such sealing face is flat. This insures a very satisfactory sealing action. The cigarette is tested during travel past the testing station, namely, when the interior of the wrapper of the cigarette C establishes a path for the flow of testing fluid from the slots 86 of the valve plate 82 and gasket 84 to the chamber 66 of the shoe 14. Testing fluid fills the recess 101 at the inner side of the diaphragm 91 whereby the latter causes the sealing element 92 to move its sealing face 94 into stronger sealing engagement with the adjoining end surface of the wrapper of the filter tip F. Thus, the testing fluid enhances the sealing action of the element 92 and connector 68.

FIGS. 4 and 5 illustrate a portion of a further sealing conveyor which is similar to the sealing conveyor 51 of FIG. 3 with the main exception that its flange 106 carries a one-piece ring-shaped deformable coupling element 111 which is a ring-shaped diaphragm overlying a ring-shaped recess 201 in the inner end face of the flange 106. This diaphragm 111 carries a full set of equidistant sealing element 112 each of which is connected with an internal tubular nipple 106a of the flange by a tubular coupling element of elastically deformable material. Each sealing element 112 is normally aligned with one row of flutes (not shown). The bores of the sealing elements 112 communicate with bind bores 116 of the flange 106, and these blind bores form part of passages which connect the bores of sealing elements 112 with a testing unit (not shown) in the same way as described in connection with FIG. 1. Thus, each bore 116 corresponds to a bore 11 of the flange 6 shown in FIG. 1. Each sealing element 112 comprises a ring-shaped washer 113 of elastically deformable material whose outer side constitutes a sealing face and can be engaged by the end surface of the wrapper of the filter tip or by the other end surface of the wrapper of the cigarette.

The operation of the conveyor shown in FIGS. 4 and 5 is analogous to that of the conveyor 51. The main difference is that the testing fluid cannot exert any pressure against the inner side of the diaphragm 111 because the interior of the recess 201 is sealed from the path for testing fluid by the elastically deformable tubular coupling elements 115. Furthermore, the sealing faces of the elements 112 (and more particularly of their washers 113) are yieldable so that they can readily follow the outline of the adjacent end surfaces of the wrappers of cigarettes. The elasticity of washers 113 enables their sealing faces to follow the outlines of uneven end surfaces. The elasticity of diaphragm 111 and of coupling elements 115 enables the sealing elements 112 to change their positions of inclination if the planes of adjoining end surfaces of the wrappers are not exactly normal to the axes of cigarettes.

The testing conveyor of FIGS. 4 and 5 may include a second sealing unit comprising the parts 18, 41, 42 of the sealing unit shown in FIG. 1. This renders it possible to supply to the conveyor filter cigarettes in such positions that the filter tips engage the washers 113 or that the filer tips engage the elements 42 of the other sealing unit.

An important advantage of my testing conveyor is that its sealing unit or units can engage and properly seal end surfaces of wrappers whose end surfaces are located in planes which are not exactly normal to the axes of cigarettes and/or uneven end surfaces (washers 113). Thus, a cigarette which is satisfactory, save for a slight deviation between actual and optimum inclination of end surfaces on its wrapper, can be properly tested and need not be segregated from perfect cigarettes. As explained above, the pivotable or universally movable sealing elements are preferably provided at the filter tipped ends of tested cigarettes because the wrappers of filter tips are sturdier than the wrappers (cigarette paper) of tobacco-containing portions of cigarettes. Still another important advantage of the testing conveyor is that its apertured sealing faces normally engage only the end surfaces of the wrapper, i.e., not the end surfaces of the filler; this insures proper sealing of wrappers even if some tobacco particles or particles of filter material extend beyond their end surfaces. The provision of apertured sealing faces wherein the diameters of apertures are only slightly less than the internal diameters of adjoining end surfaces of the wrapper further insures that the testing fluid can flow through the wrapper along a path of relatively large cross-sectional area.

It is to be noted that, through the improved conveyor has been described in connection with testing of filter cigarettes, it is equally useful for testing of plain cigarettes, plain or filter tipped cigars, cigarillos or cheroots, as well as for testing of filter rod sections.

Without further analysis, the foregoing will so fully reveal the gist of the present invention that others can, by applying current knowledge, readily adapt it for various applications without omitting features which fairly constitute essential characteristics of the generic and specific aspects of my contribution to the art.

What is claimed as new and desired to be protected by Letters Patent is set forth in the appended claims:

1. A method of testing cigarettes or analogous rodshaped articleswherein a tubular wrapper having two end surfaces surrounds a gas-permeable filler, comprising the steps of moving an article sideways between travelling first and second apertured sealing faces; moving at least said first sealing face toward the second sealing face so that each thereof engages one end surface of the wrapper therebetween; changing the inclination of at least one of said sealing faces to move it into the plane of the adjoining end surface whenever the one sealing face is in less than full contact with the adjoining end surface; and passing a testing fluid between said apertured sealing faces by way of the wrapper therebetween.

2. A method as defined in claim 1, wherein said inclination changing step comprises reducing the distance between said sealing faces to such an extent that the corresponding end surface of the wrapper changes the inclination of said one sealing face.

3. A method as defined in claim 1, wherein said sealing faces are at least slightly spaced from the respective ends of the filler upon completion of said inclination changing step so that each thereof is in substantially linear contact with the respective end of the article.

4. A method as defined in claim 1, wherein said second moving step comprises moving said first sealing face in axial direction of the article.

5. A method as defined in claim 1, wherein said second moving step comprises shifting the article axially by said first sealing face against said second sealing face.

'6. In a testing apparatus for cigarettes or analogous rod shaped articles wherein a tubular wrapper having two end surfaces surrounds a gas-permeable filler, a combination comprising a mobile conveying member having at least one receiving means positioned thereon to support an article for sidewise movement in response to movement of said conveying member; a first sealing unit provided on said conveying member and having at least one apertured sealing face adjacent to one side of said receiving means; a second sealing unit including at least one tubular sealing element having an apertured sealing face adjacent to the other side of said receiving means and deformable coupling means connecting said sealing element to said conveying member; displacing means for moving at least one of said sealing units toward the other .sealing unit during movement of said conveying member so that the end surfaces of a wrapper in said receiving means are engaged by the respective sealing faces whereby the coupling means permits the sealing face of said sealing element to move into the plane of the adjoining end surface; and means for passing a testing fluid between said sealing units by way of a wrapper in said receiving means while the end surfaces of such wrapper are engaged by the respective sealing faces.

7. A combination as defined in claim 6, wherein said conveying member is a rotor which is rotatable about a predetermined axis and wherein said receiving means extends in parallelism with said axis, said one sealing unit being movable in parallelism with said axis.

8. A combination as defined in claim 6, wherein said sealing element is rigid.

9. A combination as defined in claim 6, wherein said coupling means consists of elastic material.

10. A combination as defined in claim 6, wherein said coupling means is an elastic tube.

11. A combination as defined in claim 6, wherein said second sealing unit further comprises guide means for said sealing element, said sealing element being free to swivel with reference to said guide means.

12. A combination as defined in claim 6, wherein said sealing element is movable lengthwise of said receiving means with reference to the remainder of said second sealing unit.

13. A combination as defined in claim 6, wherein said coupling means comprises diaphragm means.

14. A combination as defined in claim 13, wherein said second sealing unit defines chamber means adjacent to one side of said diaphragm means and arranged to receive testing fluid when the latter is caused to pass between said apertured sealing faces.

15. A combination as defined in claim 6, wherein said first sealing unit comprises a plurality of first sealing faces and said second sealing unit comprises a plurality of sealing elements each aligned with one of said first sealing faces, said coupling means comprising a common coupling element for all of said sealing elements.

16. A combination as defined in claim 15, wherein said common coupling element is a diaphragm.

17. A combination as defined in claim 6, wherein said second sealing unit further comprises a tubular connectron movable by said displacing means toward and away from said receiving means, and wherein said sealing element is connected to said connector by way of said coupling means.

18. A combination as defined in claim 6, wherein said couplmg means is arranged to maintain said sealing element in a predetermined position of inclination with reference to said receiving means when the sealing face of said element is disengaged from a wrapper.

19. A combination as defined in claim 6, wherein at least one of said sealing faces is of conical shape.

20. A combination as defined in claim 6, wherein said sealing element comprises an annular portion of elastic material and wherein the sealing face of said element is provided on said annular portion.

References Cited UNITED STATES PATENTS S. CLEMENT SWISHER, Primary Examiner 

